1. Field of the Invention
The subject invention relates to oscillography and oscillographs and other recording methods and recorders, to methods and apparatus for supplying wound material from rolls of diminishing diameter and other winding and reeling methods and apparatus, to methods and apparatus for releasably retaining any one of several tubular objects of different lengths, and to combinations of such methods and apparatus.
2. Disclosure Statement
This disclosure statement is made pursuant to the duty of disclosure imposed by law and formulated in 37 CFR 1.56(a). No representation is hereby made that information thus disclosed in fact constitutes prior-art inasmuch as 37 CFR 1.56(a) relies on a materiality concept which depends on uncertain and inevitably subjective elements of substantial likelihood and reasonableness, and inasmuch as a growing attitude appears to require citation of materials which might lead to a discovery of pertinent material, though being not of themselves pertinent.
The advanced type of recording medium transport mechanism disclosed in U.S. Pat. No. 3,216,021 is typical of prior-art equipment which required the recording material to be disposed on a core with laterally projecting shafts on the supply and takeup sides. U.S. Pat. Nos. 1,531,705, 1,676,797, 3,360,210, 3,497,152, 3,539,126, and 3,720,385 proposed various winding devices and similar apparatus which in one form or another appear to share the latter drawback; impairing a desired versatility of such systems, requiring typically extra rewinding operation of the wound materials, and rendering paper or other material size changes often difficult.
In the prior-art equipment under consideration, there also exists a need for more convenient and effective supply roll mounting systems for accommodating supply rolls located on tubular supports of different lengths. In more general terms, there exists a need for methods and apparatus for releasably retaining any one of several tubular objects of different lengths.
In this respect, an early proposal according to U.S. Pat. No. 1,693,876 employs conical cable drum retaining members which are rotatably mounted on a pair of spaced standards. In practice, there existed the drawback that at least an entire standard had to be moved to accommodate cable drums of different width. To somewhat alleviate this problem, the proposal according to U.S. Pat. No. 3,955,770 mounts the coil-supporting assemblies on tracks for sliding movement toward and away from each other.
U.S. Pat. No. 3,368,769 proposed a tapered core chuck with floating key for roll retention purposes. German Utility Model Registration 7 107 188 proposed a rather bulky handwheel adjustment mechanism.
Similarly, the proposal according to British Patent Specification 1,471,361, by Dow Chemical Company, employs an air cylinder mechanism for mounting and actuating a roll retention plug. In the proposal according to U.S. Pat. No. 2,771,251, a movable chuck is biased by a compression spring which thus acts on the member to be retained. In either case, a delicate roll or tubular member would be exposed to damage. This applies also to U.S. Pat. No. 1,724,034 which employs a single bayonet joint on a spindle in conjunction with a spring-loaded barrel.
On the other hand, U.S. Pat. No. 829,185 proposed use of a bayonet joint in a device for alternatively retaining rolls of two different widths. Since that proposal used the transverse portion of an L-shaped slot for one roll width and the bottom of the longitudinal portion of that slot for the other roll width, that approach was limited in utility to one pair of rolls.
The proposal according to U.S. Pat. No. 1,702,971 employs flat paddles for supporting bolts of cloth preparatory to and during unwinding operations. One of the paddles is rotatably mounted on a standard which, together with a tubular track extending parallel to an axis through the paddles, is attached to the floor. The other paddle is rotatably mounted on a standard which, in turn, is supported on a tubular carriage riding in the mentioned tubular track. A spring has opposite ends attached to, and extends through the tubular track and carriage; biasing the carriage into the tubular track. A locking device arrests the motion of the carriage relative to the tubular track at any one of several incremental portions in order to permit an accommodation of bolts of cloth of different widths.
In so arresting the motion of the carriage, the locking device also renders the mentioned spring ineffective from exercising a biasing function on the cloth retaining paddles.
In practice, the latter drawback coupled with an only step-wise adjustability of the distance between the paddles would render that prior-art system unsuitable for releasably retaining tubular members or supply rolls of different lengths.
An infinitely adjustable spacing between supply roll retention members appear possible in the system disclosed in U.S. Pat. No. 3,104,073. However, the use of a tool and the carrying out of set screw releasing and tightening operations are then required for each change in supply roll width. A subsequent proposal according to U.S. Pat. No. 3,322,359 uses a longitudinal keyway on a support shaft to secure spring-loaded core spacers against rotational movement. A further proposal according to U.S. Pat. No. 3,941,320 appears only suitable for clamping tubular supply roll supports of a given length.
A proposal according to U.S. Pat. No. 3,792,825 uses spring clamps acting on the outside of a supply roll for retaining same in a chart drive system. That principle appears to be rather limited to the handling of perforated paper rolls. The latter patent also proposes the use of pads as braking devices. Again, there appears to be a design limitation to particular chart roll materials.
German Utility Model Registration 1 899 660 proposes use of a compression spring for side loading a retention member against a roll.
A proposal according to British Patent Specification 1,300,378 also uses a compression spring for side loading a retention member against a roll. A common problem with this and other designs using side-loading springs is that they in effect remove control of the roll retention tension from the control of the operator and, as mentioned above, tend to eventuate damage to retained rolls, especially if a firm retention of the roll is desired or required.
The proposal according to British Patent Specification 1,241,696 avoids a side-loading bias spring, but requires an elaborate carriage for mounting and placing a guide cone if rolls of different widths are to be accommodated. British Patent Specification 1,146,525 provides aligned holes in a roll support shaft and in a slidable member on which a cone-shaped roll retention member is threaded. In addition to these aligned holes, that proposal requires a pin insertable into corresponding holes for releasable retention of the slidable member. That pin has to have a handle by means of which it is inserted and removed in matching holes.
In practice, the pin may get lost and with its handle or other projecting part, expose operators to injury. Also, achievement of exact registry of the aligned holes in the slidable member with corresponding holes in the supporting shaft typically is a tedious job in practice.
German Utility Model Registration 69 08 020 proposed use of a first roll retention member attached to a shaft by a set screw and a second roll retention member having a set screw engaging a threaded jacket on the shaft, and proposed the use of several of such threaded jackets for various roll width. This would have complicated an already delicate design.
The copending patent application Ser. No. 925,498, filed July 17, 1978, now U.S. Pat. No. 4,312,006, by Lawrence Vincent Maldarelli, for Methods and Apparatus for Recording Information, Supplying Wound Materials and Retaining Tubular Objects, assigned to the subject assignee and herewith incorporated by reference herein, discloses several methods and apparatus as suggested by its title. For instance, that copending application discloses tubular member and recording medium roll retention systems wherein one of two locked retention members is resiliently biased against a retained tubular object. While that retention system performs excellently, its implementation so far has been rather expensive and the mentioned bias has tended to require a rather sturdy construction due to side loads. There thus exists a need for a less costly and typically lighter system essentially free from side load effects. A subsequent patent application, Ser. No. 06/049,537 filed June 18, 1979, now U.S. Pat. No. 4,284,995 by Gary G. Gordon, for Methods and Apparatus for Recording Information, Supplying Wound Materials and Retaining Tubular Objects, and assigned to the subject assignee addresses itself to the latter need, but for use with rolls of widely varying widths, entails lengthy threading operations.